Important news: You can now play as Samus, Link, Mega Man, or Simon Belmont in Super Mario Bros.

This is tough to resist: "Super Mario Crossover" enables you to play Super Mario Bros. using the heroes from other NES classics, including Mega Man, Samus from Metroid, Simon from Castlevania, Bill from Contra, and Link from Zelda (or, boringly, you can also use Mario). This is not just a mere cosmetic swap: the characters also retain most of their abilities. Mega Man can charge his Mega Buster, Samus can roll and dop bombs, Simon can double jump and throw axes, etc. Possibly best of all: unlike the original NES version of Super Mario Bros., you can go backwards.